Severe dry skin disorders, known as ichthyosis, are often characterized by cracks, flakes, scales, redness, etc. Less severe, but more common, moderate to mild dry skin disorders are often characterized by less severe fissures, chaps, cracks, flakes, redness, etc. Such disorders can also include inflammation and be quite painful. Typically, such disorders are treated with topical oils, hydrating emollients, ointments, etc.
The topical use of alpha-hydroxy and beta-hydroxy acids, alpha-ketoacids, and esters thereof, is well known in the art to be effective as a preventative as well as a therapeutic treatment of dry skin disorders. Treatment is generally effective at acid concentrations of about 1% to about 20% by weight. Skin irritation caused by low pH levels may be ameliorated by neutralizing the acids with a base, such as ammonium hydroxide. See, for example, U.S. Pat. No. 4,105,783 (Yu et al.).
Further, it is believed that skin penetration by such compositions is enhanced using acid/base salts. See, for example, U.S. Pat. No. 4,888,354 (Chang et al.). In addition, the topical compositions may contain additional pharmaceutical and cosmetic additives, provided they do not adversely affect the formulation, stability, and activity of the acids and/or esters. Such additives include, for example, antimicrobials, antibiotics, neoplastic agents, cardiac drugs, antihistamines, anesthetics, antipsychotics, etc. See, for example, U.S. Pat. No. 4,888,354 (Chang et al.), U.S. Pat. No. 5,420,106 (Parab), and U.S. Pat. No. 5,705,168 (Parab).
There is still a need for compositions (e.g., lotions and creams) that can be used to reduce conditions associated with dry skin and other skin disorders, such as inflammation, itching, and/or pain relief.